Triangles - GMATPrep Test 1

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by Anurag@Gurome » Wed Feb 22, 2012 6:44 pm
kwah wrote:I have attached a question from GMATPrep Test 1.

Answer: A

Can someone please explain steps to achieve this result?

Thank you
Area of a triangle when coordinates of the vertices are (x1, y2), (x2, y2), and (x3, y3) = 1/2 |x1(y2 - y3) + x2(y3 - y1) + x3(y1 - y2)|
P(4, 0), Q(0, 3), R(7, 4)
So, here area of triangular region = (1/2)|4(3 - 4) + 0(4 - 0) + 7(0 - 3)| = (1/2)|-4 - 21| = 12.5 sq units

The correct answer is A.

You can also find area using the distance formula.
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by GMATGuruNY » Thu Feb 23, 2012 5:10 am
I posted a very efficient approach here:

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by kwah » Thu Feb 23, 2012 9:17 pm
Thank you Anurag@Gurome and GMATGuruNY for helping me with this question. It is most helpful.

Would you advise to draw out figures and include the letters when tackling these kind of questions or is it a waste of time?

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by Anurag@Gurome » Thu Feb 23, 2012 9:22 pm
kwah wrote:Thank you Anurag@Gurome and GMATGuruNY for helping me with this question. It is most helpful.

Would you advise to draw out figures and include the letters when tackling these kind of questions or is it a waste of time?
My view: In some questions, drawing figures really help you and definitely visualizing the scenario helps you solve it in a better way.
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